trasborg Kaiser M715 - radiator Hose - Photo 9290629

If you've swapped radiator hoses, did you swap the wire too? That wire, which most of us hate, is really a necessary evil. The feed hose (opposite the return hose from the engine) can collapse from suction at higher rpm if there is no spring or wire in it. You'll need to go junkyard fishing if you don't have one. We have made them out of coat hangers in the past in a pinch.